RESUMO
OBJECTIVES: Despite representing an important component of current dental adhesives, HEMA has been said to negatively influence the long-term stability of adhesion to dentine and enamel. The aim of this randomised clinical trial was to evaluate the 3-year clinical performance of two one-step self-etch adhesives. METHODS: Thirty patients had 175 non-carious cervical lesions restored with composite (Gradia Direct Anterior, GC) using either the HEMA-rich adhesive Clearfil Tri-S Bond (C3S; Kuraray) or the HEMA-free adhesive G-Bond (GB; GC). The restorations were evaluated by two examiners at baseline, 6, 12, 24 and 36 months regarding retention, caries recurrence, marginal integrity and discoloration and post-operative sensitivity. The data were statistically analysed with GEE and McNemar tests (p<0.05). RESULTS: The recall rate at 6 and 12 months was 100% and decreased to 96.7% at 24 and 36 months. At 3 years, the retention rate was 93.8% for C3S and 98.8% for GB (p=0.14). A pairwise comparison showed no significant differences between the two adhesives for all the parameters evaluated, irrespective of the recall (p>0.05). After 3 years, both adhesives presented an increase in the percentage of clinically acceptable marginal discoloration (C3S: 32.9% and GB: 26.8%) normally associated to clinically acceptable marginal defects (C3S: 35.8% and GB: 26.5%). Only 1 dentine margin of a GB restoration presented a severe marginal defect (1.2%) and 1 C3S restoration presented caries recurrence. The overall 3-year clinical success rate was 92.6% for C3S and 97.6% for GB (p=0.16). CONCLUSION: Both one-step self-etch adhesives presented an equally favourable clinical effectiveness at 3 years. CLINICAL SIGNIFICANCE: HEMA is a monomer frequently present in dental adhesives in order to increase their wettability and hydrophilicity. However, this monomer negatively influences hydrolytic stability and durability of the adhesive interface complex. In this 3-year clinical trial no significant difference in bonding effectiveness was noticed between a HEMA-rich and HEMA-free one-step adhesive.
Assuntos
Restauração Dentária Permanente/métodos , Adesivos Dentinários/química , Colo do Dente/patologia , Desgaste dos Dentes/terapia , Adulto , Idoso , Cor , Resinas Compostas/química , Colagem Dentária , Cárie Dentária/etiologia , Adaptação Marginal Dentária , Materiais Dentários/química , Dentina/patologia , Sensibilidade da Dentina/etiologia , Feminino , Seguimentos , Humanos , Masculino , Metacrilatos/química , Pessoa de Meia-Idade , Recidiva , Cimentos de Resina/química , Propriedades de Superfície , Descoloração de Dente/etiologia , Resultado do Tratamento , Adulto JovemRESUMO
Genetic reprogramming of adult cells to generate induced pluripotent stem (iPS) cells is a new and important step in sidestepping some of the ethical issues and risks involved in the use of embryonic stem cells. iPS cells can be generated by introduction of transcription factors, such as OCT4, SOX2, KLF4, and CMYC. iPS cells resemble embryonic stem cells in their properties and differentiation potential. The mechanisms that lead to induced pluripotency and the effect of each transcription factor are not completely understood. We performed a critical evaluation of the effect of overexpressing OCT4 in mesenchymal stem cells and fibroblasts and found that OCT4 can activate the expression of other stemness genes, such as SOX2, NANOG, CMYC, FOXD3, KLF4, and ßCATENIN, which are not normally or are very weakly expressed in mesenchymal stem cells. Transient expression of OCT4 was also performed to evaluate whether these genes are affected by its overexpression in the first 48 h. Transfected fibroblast cells expressed around 275-fold more OCT4 than non-transfected cells. In transient expression, in which cells were analyzed after 48 h, we detected only the up-regulation of FOXD3, SOX2, and KLF4 genes, suggesting that these genes are the earlier targets of OCT4 in this cellular type. We conclude that forced expression of OCT4 can alter cell status and activate the pluripotent network. Knowledge gained through study of these systems may help us to understand the kinetics and mechanism of cell reprogramming.
Assuntos
Fibroblastos/metabolismo , Expressão Gênica , Células-Tronco Mesenquimais/metabolismo , Fator 3 de Transcrição de Octâmero/genética , Linhagem Celular Tumoral , Células Cultivadas , Perfilação da Expressão Gênica , Humanos , Fator 4 Semelhante a Kruppel , Fator 3 de Transcrição de Octâmero/metabolismo , Transdução GenéticaRESUMO
BACKGROUND: Racemic [RS(+/-)] bupivacaine can be associated with severe cardiotoxicity. The S(-) isomer is known to be less neuro- and cardiotoxic, but demonstrates a lower potency to block motor activity than RS(+/-) bupivacaine. Thus, the potency and toxicity of a non-racemic bupivacaine mixture were studied. METHODS: Gastrocnemic muscle twitches induced by electrical stimulation of sciatic nerves in rats were used to compare the impact by bupivacaine solutions on motor activity. Field stimulation at 1 Hz eliciting ventricular muscle twitches was used to investigate the effects on cardiac contractility. The lethal dose of each local anesthetic agent was determined following drug infusions during general anesthesia in mechanically ventilated rats. RESULTS: Non-racemic (75S:25R) bupivacaine was more potent (P<0.05) than S(-) or R(+) enantiomers to block motor nerve activity. The concentrations of RS(+/-), 75S:25R, R(+) and S(-) bupivacaine to inhibit nerve conduction by 50% were 0.84 (0.37- 2.20), 0.84 (0.47-2.48), 2.68 (0.98-3.42) and 2.11 mM (1.5-4.03), respectively. Pronounced reductions in ventricular muscle twitches were observed with RS(+/-) and R(+) bupivacaine at low concentrations (0.5-4 microM). Lethal doses for 75S:25R (39.9 mg kg(-1)), and S(-) (34.7 mg kg(-1)) were higher (P<0.05) than for R(+) (16.2 mg kg(-1)) and RS(+/-) bupivacaine (18.4 mg kg(-1)), respectively. DISCUSSION: The potency of S(-) bupivacaine to block the motor activity in the sciatic nerve was enhanced when 25% of the S(-) isomer was replaced by the antipode R(+) bupivacaine. This effect was not associated with increased toxicity.
Assuntos
Anestésicos Locais/farmacologia , Bupivacaína/farmacologia , Neurônios Motores/efeitos dos fármacos , Bloqueio Nervoso , Anestésicos Locais/química , Anestésicos Locais/toxicidade , Animais , Bupivacaína/química , Bupivacaína/toxicidade , Coração/efeitos dos fármacos , Técnicas In Vitro , Contração Isométrica/efeitos dos fármacos , Dose Letal Mediana , Músculo Liso/efeitos dos fármacos , Músculo Liso Vascular/efeitos dos fármacos , Músculo Liso Vascular/inervação , Ratos , Ratos Wistar , Nervo Isquiático/efeitos dos fármacos , Nervo Isquiático/fisiologia , EstereoisomerismoRESUMO
We have reviewed more than a decade of clinical-echographical research in the developmental displasia of the hip (D.D.H.). We have examined 2050 small patients aged less than three months, with normal hips, and evaluated a number of ultrasound parameters that, in our opinion, may be helpful to give a description of hips particularly precise. We clearly underline that a precise definition, as more as possible, is a starting point to study all the pathological hips.
Assuntos
Luxação Congênita de Quadril/diagnóstico por imagem , Quadril/diagnóstico por imagem , Feminino , Humanos , Lactente , Recém-Nascido , Masculino , Valores de Referência , UltrassonografiaRESUMO
The purpose of this study was to compare the microleakage of class V cavities restored with composite resin (CR), resin-modified glass ionomer cement (RMGIC) and polyacid-modified resin composite (PAMRC), using different clinical procedures. Thirty-six noncarious human molars were used in this study. A class V cavity, measuring approximately 3 mm x 4 mm x 2 mm, was prepared in each tooth in both buccal and lingual aspects, with a diamond bur (number 1,093) at high speed, with coolant water spray. The occlusal margin was located on enamel and the gingival margin was located on dentin. The teeth were divided into 9 groups with 8 specimens each. The cavities were restored according to different techniques. The specimens from groups 1, 2, 4 and 5 did not receive acid etching. The samples were stored in water at 37 degrees C for 24 hours, subjected to occlusal load, thermocycled and immersed in rhodamine B. The restorations were then washed and sectioned in buccolingual direction. The depth of dye penetration was scored from zero (no leakage) to 3 (maximum leakage). The Kruskal-Wallis test revealed statistically significant differences between the materials (p < 0.05). PAMRC used without acid etching showed the greatest score of leakage in both margins. In the gingival margin, CR showed scores of leakage lower than those of PAMRC and RMGIC. Additional retentions and acid etching were able to decrease microleakage in PAMRC restorations in both gingival and occlusal margins.
Assuntos
Compômeros , Resinas Compostas , Cárie Dentária/terapia , Infiltração Dentária/etiologia , Restauração Dentária Permanente/efeitos adversos , Cárie Dentária/classificação , Humanos , Técnicas In VitroRESUMO
The inhibitory role of NO on sympathetic-induced contraction of resistance vessels of spontaneously hypertensive rats (SHR) has not been defined. Accordingly, we investigated the effect of endothelial removal or NO synthase inhibition on vasoconstrictor responses to sympathetic stimulation or phenylephrine in perfused mesenteric beds isolated from normotensive rats (NR) and SHR. Electrical stimulation (10 to 64 Hz) of perivascular nerves elicited a frequency-dependent increase in perfusion pressure that was greater in preparations from SHR (maximal effect: 223.4+/-8.4 versus 117.6+/-10.3 mm Hg in NR, n=6, P<0.001), and endothelium removal did not affect these responses in arteries from NR but caused a significant shift to the left of the frequency-response curve in arteries from SHR. In arteries with endothelium, inhibition of NO synthase with N(G)-nitro-L-arginine (L-NNA, 50 micromol/L) augmented the vasoconstrictor responses to sympathetic stimulation in both NR and SHR preparations. In preparations that had the endothelium removed, however, L-NNA potentiated only the responses to sympathetic stimulation of NR arteries. Vasoconstrictor responses to phenylephrine was potentiated by endothelium removal and in the presence of L-NNA only when the endothelium was intact in both NR and SHR arteries. The number of NADPH-diaphorase-positive cells in the superior mesenteric sympathetic ganglion of SHR was significantly less compared with that of NR. In conclusion, these data suggest a prejunctional inhibitory action of non-endothelial-derived NO, most probably neuronal-derived NO, on sympathetic-mediated vasoconstriction in NR arteries. In contrast, enhancement of the sympathetic-mediated vasoconstriction in SHR arteries elicited by L-NNA can be attributed to inhibition of endothelial-derived NO.
Assuntos
Endotélio Vascular/fisiologia , Hipertensão/fisiopatologia , Artérias Mesentéricas/fisiologia , Óxido Nítrico/antagonistas & inibidores , Vasoconstrição/fisiologia , Animais , Pressão Sanguínea/fisiologia , Inibidores de Ciclo-Oxigenase/farmacologia , Relação Dose-Resposta a Droga , Estimulação Elétrica , Inibidores Enzimáticos/farmacologia , Feminino , Técnicas In Vitro , Indometacina/farmacologia , Óxido Nítrico/fisiologia , Óxido Nítrico Sintase/antagonistas & inibidores , Nitroarginina/farmacologia , Fenilefrina/farmacologia , Ratos , Ratos Endogâmicos SHR , Ratos Wistar , Vasoconstritores/farmacologiaRESUMO
Glucocorticoids have been used in the treatment of a variety of inflammatory processes including autoimmune diseases. However, the influence of low-dose glucocorticoids on the respiratory burst activity of neutrophils has not been studied. The aim of this work was to study the effect of treatment with low-dose prednisone on the oxidative burst of rat peripheral blood neutrophils. Wistar male rats were treated with prednisone by gavage (28, 87 or 257 microg/animal/day) for 7 or 15 days. These doses are equivalent to 10, 30 or 90 mg/adult human ( approximately 70 kg)/day, respectively. Sera from normal rats were used to opsonize zymosan (opZy). Neutrophils (1x10(5)) were stimulated by opZy and the oxidative burst of control or treated rat cells was measured by luminol-dependent chemiluminescence (CL). Prednisone did not affect the CL of rat neutrophils for either period of treatment, or any studied doses, when compared with controls. These results suggest that the low-dose prednisone has no effect on the oxidative burst mediated by complement receptors during the rat neutrophil phagocytosis of complement-opZy.
Assuntos
Neutrófilos/efeitos dos fármacos , Neutrófilos/metabolismo , Prednisona/administração & dosagem , Receptores de Complemento/fisiologia , Explosão Respiratória/efeitos dos fármacos , Animais , Relação Dose-Resposta a Droga , Esquema de Medicação , Intubação Gastrointestinal , Cinética , Medições Luminescentes , Masculino , Neutrófilos/imunologia , Ratos , Ratos Wistar , Explosão Respiratória/imunologiaRESUMO
This work investigated the correlation between serum levels of factor B, AP-lytic activity, ratio of factor B activation by zymosan, and AP-dependent neutrophil phagocytosis in samples of normal human serum (NHS). In addition, since the antithyroid drug propylthiouracil (PTU) induces increased levels of AP lytic activity in rats, groups of these animals were treated with this drug in order to increase AP titers and to evaluate those parameters also in this condition. The results showed no correlation between factor B concentration and AP lytic activity in 18 samples of NHS or between factor B concentration and proportion of consumption by zymosan. Interestingly, this consumption was also not correlated with phagocytosis as measured by the chemiluminescence (CL) response of neutrophils to the opsonized particles. The two biological properties of phagocytosis and lytic activity, dependent of AP, were not correlated to each other in the NHS samples. In the samples of rat serum with increased AP lytic levels a different result was observed. A positive correlation between CL response and lytic activity occurred in serum of animals receiving a low PTU dose, but not in serum of animals receiving a high dose, where CL responses were lower than those of controls. The results are compared to literature data and discussed in terms of individual differences in resistance or susceptibility to infections and or diseases involving the complement system.
Assuntos
Fator B do Complemento/metabolismo , Via Alternativa do Complemento/imunologia , Hemólise/imunologia , Neutrófilos/imunologia , Fagocitose/imunologia , Animais , Antitireóideos/farmacologia , Via Alternativa do Complemento/efeitos dos fármacos , Relação Dose-Resposta Imunológica , Eritrócitos/imunologia , Feminino , Hemólise/efeitos dos fármacos , Humanos , Medições Luminescentes , Neutrófilos/efeitos dos fármacos , Proteínas Opsonizantes/imunologia , Fagocitose/efeitos dos fármacos , Propiltiouracila/farmacologia , Coelhos , Ratos , Zimosan/farmacologiaRESUMO
The cholelithiasis is a unusual pathology of paediatric age; it is exceptional pathology in the earliest childhood. The disease is often unsymptomatic and it can be correlated with several pathologies. The echography is the golden standard. We describe three cases with different peculiarities.
Assuntos
Colelitíase/diagnóstico por imagem , Criança , Colecistectomia , Colecistite/etiologia , Colelitíase/complicações , Colelitíase/cirurgia , Feminino , Humanos , Masculino , Resultado do Tratamento , UltrassonografiaRESUMO
In order to identify early abnormalities in non-insulin-dependent diabetes mellitus (NIDDM) we determined insulin (using an assay that does not cross-react with proinsulin) and proinsulin concentrations. The proinsulin/insulin ratio was used as an indicator of abnormal beta-cell function. The ratio of the first 30-min increase in insulin to glucose concentrations following the oral glucose tolerance test (OGTT; I30-0/G30-0) was taken as an indicator of insulin secretion. Insulin resistance (R) was evaluated by the homeostasis model assessment (HOMA) method. True insulin and proinsulin were measured during a 75-g OGTT in 35 individuals: 20 with normal glucose tolerance (NGT) and without diabetes among their first-degree relatives (FDR) served as controls, and 15 with NGT who were FDR of patients with NIDDM. The FDR group presented higher insulin (414 pmol/l vs 195 pmol/l; P = 0.04) and proinsulin levels (19.6 pmol/l vs 12.3 pmol/l; P = 0.03) post-glucose load than the control group. When these groups were stratified according to BMI, the obese FDR (N = 8) showed higher fasting and post-glucose insulin levels than the obese NGT (N = 9) (fasting: 64.8 pmol/l vs 7.8 pmol/l: P = 0.04, and 60 min post-glucose: 480.6 pmol/l vs 192 pmol/l: P = 0.01). Also, values for HOMA (R) were higher in the obese FDR compared to obese NGT (2.53 vs 0.30; P = 0.075). These results show that FDR of NIDDM patients have true hyperinsulinemia (which is not a consequence of cross-reactivity with proinsulin) and hyperproinsulinemia and no dysfunction of a qualitative nature in beta-cells.
Assuntos
Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/genética , Insulina/sangue , Proinsulina/sangue , Adulto , Diabetes Mellitus Tipo 2/diagnóstico , Feminino , Teste de Tolerância a Glucose , Humanos , Insulina/metabolismo , Secreção de Insulina , Masculino , Pessoa de Meia-Idade , Fatores de RiscoRESUMO
In order to identify early abnormalities in non-insulin-dependent diabetes mellitus (NIDDM) we determined insulin (using an assay that does not cross-react with proinsulin) and proinsulin concentrations. The proinsulin/insulin ratio was used as an indicator of abnormal ß-cell function. The ratio of the first 30-min increase in insulin to glucose concentrations following the oral glucose tolerance test (OGTT; I30-0/G30-0) was taken as an indicator of insulin secretion. Insulin resistance (R) was evaluated by the homeostasis model assessment (HOMA) method. True insulin and proinsulin were measured during a 75-g OGTT in 35 individuals: 20 with normal glucose tolerance (NGT) and without diabetes among their first-degree relatives (FDR) served as controls, and 15 with NGT who were FDR of patients with NIDDM. The FDR group presented higher insulin (414 pmol/l vs 195 pmol/l; P = 0.04) and proinsulin levels (19.6 pmol/l vs 12.3 pmol/l; P = 0.03) post-glucose load than the control group. When these groups were stratified according to BMI, the obese FDR (N = 8) showed higher fasting and post-glucose insulin levels than the obese NGT (N = 9) (fasting: 64.8 pmol/l vs 7.8 pmol/l; P = 0.04, and 60 min post-glucose: 480.6 pmol/l vs 192 pmol/l; P = 0.01). Also, values for HOMA (R) were higher in the obese FDR compared to obese NGT (2.53 vs 0.30; P = 0.075). These results show that FDR of NIDDM patients have true hyperinsulinemia (which is not a consequence of cross-reactivity with proinsulin) and hyperproinsulinemia and no dysfunction of a qualitative nature in ß-cells
Assuntos
Feminino , Humanos , Adulto , Pessoa de Meia-Idade , Diabetes Mellitus Tipo 2/sangue , Teste de Tolerância a Glucose , Insulina/sangue , Proinsulina/sangue , Anticorpos Monoclonais , Diabetes Mellitus Tipo 2/diagnóstico , Fluorimunoensaio , Resistência à Insulina/genética , Insulina/metabolismo , Ilhotas Pancreáticas/fisiopatologia , Fatores de RiscoRESUMO
Relatamos um caso de diagnostico pre-natal de rubeola congenita. Apos o nascimento, alem da confirmacao feita atraves do exame fisico e sorologico do recem-nascido, o virus tambem pode ser demonstrado no primeiro fluido aspirado da orofaringe do recem-nascido, utilizando-se a reacao em cadeia da polimerase (PCR). Sugerimos que este fluido (colhido rotineiramente no momento da reanimacao neonatal) possa ser utilizado na pesquisa de outros agentes infecciosos, que nao sao facilmente identificados por outros metodos
Assuntos
Humanos , Feminino , Gravidez , Adulto , Recém-Nascido , Reação em Cadeia da Polimerase , Rubéola (Sarampo Alemão)/congênito , Diagnóstico Pré-Natal , SucçãoRESUMO
Studies on the association between vitamin D receptor (VDR) polymorphism and bone mineral density (BMD) in different populations have produced conflicting results probably due to ethnic differences in the populations studied. The Brazilian population is characterized by a very broad genetic background and a high degree of miscegenation. Of an initial group of 164, we studied 127 women from the city of São Paulo, aged 20 to 47 years (median, 31 years), with normal menses, a normal diet and no history of diseases or use of any medication that could alter BMD. VDR genotype was assessed by PCR amplification followed by BsmI digestion of DNA isolated from peripheral leukocytes. BMD was measured using dual energy X-ray absorptiometry (Lunar DPX) at the lumbar site (L2-L4) and femoral neck. Most of the women (77.6%) were considered to be of predominantly European ancestry (20.6% of them reported also native American ancestry), 12.8% were of African-Brazilian ancestry and 9.6% of Asian ancestry, 41.0% (52) were classified as bb, 48.8% (62) as Bb and 10.2% (13) as BB. The BB, Bb and bb groups did not differ in age, height, weight, body mass index or age at menarche. Lumbar spine BMD was significantly higher in the bb group (1.22 +/- 0.16 g/cm2) than in the BB group (1.08 +/- 0.14; P < 0.05), and the Bb group presented an intermediate value (1.17 +/- 0.15). Femoral neck BMD was higher in the bb group (0.99 +/- 0.11 g/cm2) compared to Bb (0.93 +/- 0.12) and BB (0.90 +/- 0.09) (P < 0.05). These data indicate that there is a significant correlation between the VDR BsmI genotype and BMD in healthy Brazilian premenopausal females.
Assuntos
Alelos , Densidade Óssea/fisiologia , Pré-Menopausa/fisiologia , Receptores de Calcitriol/genética , Adulto , Brasil , Feminino , HumanosRESUMO
Studies on the association between vitamin D receptor (VDR) polymorphism and bone mineral density (BMD) in different populations have produced conflicting results probably due to ethnic differences in the populations studied. The Brazilian population is characterized by a very broad genetic background and a high degree of miscegenation. Of an initial group of 164, we studied 127 women from the city of Spo Paulo, aged 20 to 47 years (median, 31 years), with normal menses, a normal diet and no history of diseases or use of any medication that could alter BMD. VDR genotype was assessed by PCR amplification followed by BsmI digestion of DNA isolated from peripheral leukocytes. BMD was measured using dual energy X-ray absorpitometry (Lunar DPX) at the lumbar site (L2-L4) and femoral neck. Most of the women (77.6 per cent) were considered to be of predominantly European ancestry (20.6 per cent of them reported also native American ancestry), 12.8 per cent were of African-Brazilian ancestry and 9.6 per cent of Asian ancestry, 41.0 per cent (52) were classified as bb, 48.8 per cent (62) as Bb and 10.2 per cent (13) as BB. The BB, Bb and bb groups did not differ in age, height, weight, body mass index or age at menarche, Lumbar spine BMD was significantly higher in the bb group (1.22 + 0.16 g/cm2) than in the BB group (1.08 + 0.14; P<0.05), and the Bb group presented an intermediate value (1.17 + 0.15). Femoral neck BMD was higher in the bb group (0.99 + 0.11 g/cm2) compared to Bb (0.93 + 0.12) and BB (0.90 + 0.09) (P<0.05). These data indicate that there is a significant correlation between the VDR BsmI genotype and BMD in healthy Brazilian premenopausal females.
Assuntos
Feminino , Humanos , Adulto , Alelos , Densidade Óssea/fisiologia , Pré-Menopausa/fisiologia , Receptores de Calcitriol/genética , BrasilRESUMO
We present a case of prenatal diagnosis of congenital rubella. After birth, in addition to traditional serologic and clinical examinations to confirm the infection, we could identify the virus in the "first fluid aspirated from the oropharynx of the newborn", using polimerase chain reaction (PCR). We propose that this first oropharynx fluid (collected routinely immediately after birth) could be used as a source for identification of various congenital infection agents, which may not always be easily identified by current methods.
Assuntos
Orofaringe/virologia , Reação em Cadeia da Polimerase , Síndrome da Rubéola Congênita/diagnóstico , Adulto , Feminino , Humanos , Recém-Nascido , Masculino , Orofaringe/metabolismo , Gravidez , Complicações Infecciosas na Gravidez/diagnóstico , Diagnóstico Pré-Natal , RNA Viral/isolamento & purificaçãoRESUMO
This study of the Japanese-Brazilians living in Bauru, Sao Paulo, Brazil, aimed at determining the prevalence of DM in the first (Issei) and second (Nisei) generations, according to WHO criteria. Insulin and proinsulin were determined by new immunofluorimetric assays (IMFA), that measure true insulin and intact proinsulin, at fasting and 2 h after glucose load. The data showed a very scattered distribution, so only medians are shown and no statistical testing applied. There was a tendency for higher proinsulin levels in the diabetic groups. The highest fasting proinsulin levels were seen in the diabetic patients, either obese or non-obese. The post-load insulin levels were higher in diabetic and IGT individuals, compared to normals. Both generations showed a distinct behaviour for the obese and non-obese groups, and no major differences were observed between generations. This population seems to be sensitive to environmental changes, since the obese groups showed the higher levels of proinsulin and insulin. In the evaluation of the role of the environmental factors in the pathogenesis of DM, proinsulin and insulin levels could act as early markers of pancreatic dysfunctions.
Assuntos
Diabetes Mellitus/etnologia , Insulina/sangue , Proinsulina/sangue , Adulto , Idoso , Índice de Massa Corporal , Brasil , Diabetes Mellitus/sangue , Diabetes Mellitus/prevenção & controle , Jejum/sangue , Fluorimunoensaio , Teste de Tolerância a Glucose , Humanos , Japão/etnologia , Pessoa de Meia-Idade , Obesidade , PrevalênciaRESUMO
To determine whether proinsulin (PI) contributes significantly to the immunoreactive insulin (IRI) concentrations in acromegalics, we measure PI, "true insulin" and IRI in a group of acromegalics compared with a control group. Serum PI was determined by the immunofluorimetric assay (IFMA). Insulin was also determined by an IFMA that measures true insulin and by a radioimmunoassay (RIA). We performed an oral glucose tolerance test (OGTT) in a total group of 46 subjects: 10 controls with normal OGTT and body mass index < 25 kg/m2 (control group I), 10 controls with normal OGTT and body mass index > 25 kg/m2 (control group II), 15 patients with active acromegaly and normal OGTT and 11 patients with active acromegaly and IGT. Plasma glucose, serum GH, insulin and proinsulin were measured in all OGTT samples. Basal levels of insulin-like growth factor I (IGF-I) were measured in acromegalics. Mean body mass index in acromegalics with normal and impaired glucose tolerance were significantly higher compared with control group I and similar when compared with control group II. Proinsulin increased during OGTT in acromegalics with impaired glucose tolerance compared to control group I, and only fasting proinsulin compared to control group II. In normal OGTT acromegalics, only fasting proinsulin was increased. The RIA insulin during OGTT was significantly higher for both acromegalic groups compared to control group I and only at fasting when compared with control group II. This difference was not evident when insulin was measured by IFMA. These results suggest that in acromegalics, hyperinsulinism measured by RIA was at least in part due to hyperproinsulinism.
Assuntos
Acromegalia/sangue , Insulina/sangue , Proinsulina/sangue , Adulto , Idoso , Glicemia/análise , Índice de Massa Corporal , Feminino , Fluorimunoensaio , Teste de Tolerância a Glucose , Hormônio do Crescimento/sangue , Humanos , Cinética , Masculino , Pessoa de Meia-Idade , RadioimunoensaioRESUMO
OBJECTIVE: To evaluate the prevalence of IgG antibodies to bovine serum albumin (BSA) in a cohort of Brazilian children and young adults with IDDM. RESEARCH DESIGN AND METHODS: Sera from 81 subjects with < 1 year of IDDM (group 1), III subjects with > 1 year of IDDM (group 2), and 207 normoglycemic subjects were tested using an immunofluorimetric assay. A receiver-operating-characteristic curve was used to establish the threshold of anti-BSA antibody titers defining the positivity of the assay. RESULTS: The distribution of the fluorimetric index (FI) of anti-BSA antibodies did not have a gaussian profile. Rank sum of FI was significantly higher in patients than in control subjects (P < 0.0001). Average logFI values of both IDDM groups were significantly higher than that of the control group (P < 0.005 for both groups). There was a trend toward higher FI levels in group 1 than in group 2 (P = 0.06). A FI cutoff of 0.7 optimized the ratio of true-positive to false-positive of the assay, with the best equilibrium between sensitivity and specificity. The prevalence of anti-BSA antibodies was 52% in group 1, 47% in group 2, and 28% in the control group (P = 0.0001). An independent association between anti-BSA antibodies and IDDM, with an odds ratio of 3.03 (P < 0.0001), was observed in a logistic regression analysis. However anti-BSA antibodies explained only 5% of the variability of IDDM versus NIDDM. CONCLUSIONS: Our results confirm that the prevalence of anti-BSA antibodies is higher in IDDM subjects than in control subjects, even after 1 year of diabetes. However, a large overlap of antibody titers is observed in patients and control subjects, suggesting that anti-BSA antibodies are neither sensitive nor specific markers of IDDM.
Assuntos
Anticorpos/sangue , Diabetes Mellitus Tipo 1/imunologia , Soroalbumina Bovina/imunologia , Adolescente , Adulto , Brasil , Criança , Diabetes Mellitus Tipo 1/sangue , Diabetes Mellitus Tipo 2/sangue , Diabetes Mellitus Tipo 2/imunologia , Reações Falso-Positivas , Feminino , Humanos , Masculino , Valores de Referência , Análise de Regressão , Sensibilidade e Especificidade , Estatísticas não ParamétricasRESUMO
We describe a time-resolved fluoroimmunoassay specific for human proinsulin using a combination of two high-affinity monoclonal antibodies, one against insulin and the other specific for intact proinsulin and for split 65-66 and des 64-65 proinsulin forms. The assay employs only 200 microl of serum, with a detection limit of 0.1 pmol/l. The intra-assay variation coefficient was less than 3% between 3 and 1000 pmol/l. There was 0% cross-reaction with insulin, C-peptide, split 32-33 and des 31-32 proinsulin. Serum concentration of proinsulin was analyzed in 50 subjects during an oral glucose tolerance test (10 non-obese control, 10 obese controls, 10 subjects with impaired glucose tolerance, 10 patients with type II diabetes mellitus (DM) and fasting blood glucose (FBG) < 140 mg/dl, and 10 patients with type II DM and FBG > 150 mg/dl). Mean fasting serum proinsulin levels measured by this assay in non-obese controls (0.84 - 0.90 pmol/l; 0.1-2.4 pmol/l) were lower than the results reported by other investigators. There was an increase of proinsulin related to obesity and increased glucose levels, suggesting that proinsulin levels increase with insulin resistance.